This invention relates to compositions which are specifically adapted for the purification of water. More particularly, the present invention is directed to water contaminant adsorption compositions which consist of a plurality of components and which are adapted for the removal of organic, inorganic and microbiological contaminants in water.
There is a growing concern amongst individuals and in industry with regard to the quality of the water that they are receiving. In many industries the water that is needed for certain processes must be of a very high quality. This is the case in such industries as medical laboratories, analytical laboratories and in the production of high quality electronic components. However, as this need for higher quality water is increasing there is a continual deterioration in the quality of the water that is available in many water supplies. This has become essentially a nationwide problem.
There is also considerable concern amongst individuals with regard to the water that they are receiving in their homes for consumption. This is also a concern in office and other commercial buildings. Many water utilities draw their water supplies from lakes and rivers into which various substances, including pollutants, are being flowed. It is true that these various pollutants will get diluted down to what is considered a safe level, but there is a concern today with regard to what exactly is a safe level for any particular contaminant in a water supply. There is also the problem that water will pickup metal contaminants from the piping distribution system. This includes lead and other heavy metals. In all honesty there is no hard data with regard to a safe amount of any contaminant that can be consumed. As a result there has been an increased usage of bottled water by many people for drinking water purposes and there has been the incorporation of water conditioning devices in home plumbing systems in order to assure a purified source of drinking water.
The present invention is directed to providing purified water for both industrial usages, commercial usages and for home usages. The objective is to remove by adsorption, or to remove catalytically, various elements and compounds, algae and bacteria, turbidity resulting from suspended matter, products of decayed vegetation, chemical waste, organic pesticides, sediment, metals including heavy metals, rust and silt from a water that is being received either from a well source or from a city water source. The present adsorbent compositions are able to handle contaminants at a high concentration levels. The present contaminant adsorption composition can adsorb over 97 percent of the organics contained in a water supply and can also remove more than 80 percent of the lead or other heavy metal that is contained in that water supply. In addition the adsorption composition will remove over 99.9 percent of elemental chlorine that is in the water supply.
The listing of the various contaminants that can be removed from a water source is quite lengthy. Needless to say it includes all of the major contaminant metals such as arsenic and lead, the various halocarbons which includes the various chlorocarbons and other halocarbons as well as the various aromatic organic substances such as benzene, toluene, styrene and ethyl benzene. The scope of the removal of such substances is to such an extent and to such a degree that there results a very high purified water which exits from the present adsorbent compositions.
Adsorption is not a new technique for removing various contaminants from water. Various fine solid materials have been utilized in the treatment of water. These have been utilized to remove fine solids from water and to remove discoloration from water. Such materials that have been used include various clays as well as activated carbons. In this regard in U.S. Pat. No. 3,278,040 there is disclosed a particular attapulgite clay filter aid product. This improved attapulgite clay with a flux mixture of alkali metal polyphosphate, and in particular sodium polyphosphate, sodium hydroxide, and lime. In the formation of this improved attapulgite clay filter aid the alkali metal polyphosphate and the sodium hydroxide are incorporated with the clay the with the clay then being in the form of a dilute aqueous colloidal suspension. The lime is then incorporated into the clay and the aqueous dispersion is dried to a solid condition. After being dried the composition is calcined at a high temperature. The result is an improved filter aid which can be used in various chemical processes.
In U.S. Pat. No. 3,420,709 there is disclosed a method for purifying a liquid which consists of contacting the liquid with an insoluble synthetic resin, such as an ion-exchange resin, and then contacting the liquid with an adsorbent such as activated carbon. In this patent there is disclosed a two step technique for liquid purification. The objective of this patent is to provide a system that is capable of purifying water and other liquids. In particular the process is directed to the purification of substances that are to be used as foods. In a preferred embodiment the disclosed invention contains as the principal adsorbent an activated carbon and as the complementary adsorbent an ion-exchange resin. The ion-exchange resin can be a cationic or an anionic ion-exchange resin. The disclosure of this patent is interesting, however there is set forth a fairly complex technique for purifying water and other liquids.
In U.S. Pat. No. 3,545,622 there is disclosed a permeable filter and drier block which consists of a silica gel and other inorganic desiccants, such as sodium aluminum silicate bound together into a self-supporting block. The silica gel and other inorganic desiccant are bound together into the block by means of an organic binder such as an epoxy resin or a polyvinyl alcohol resin. These compositions are primarily used as drying agents in systems such as refrigeration systems. However, they will also remove various other substances than water.
U.S. Pat. No. 3,784,014 discloses a waste and water treatment system. As a part of the waste and water treatment system there is a plurality of filtration columns. The filtration columns include a bimetallic medium which separates particles electrophoretically. That is, the filtration columns will contain substances such as electrically conductive metallic aluminum powder and electrically conductive carbon granules. The number of adsorption columns in the system will depend on the size of the system. However in general the system will include three different columns. The first column will contain aluminum powder which has a 20 to 50 mesh. In this column various suspended materials are coagulated and removed. The liquid then goes to a second stripper column. The stripper column will contain a mixture of aluminum powder and granular carbon. This column is in the nature of a galvanic cell. This column removes various ions remaining in the solution. The liquid then flows to a third column which contains activated carbon. The activated carbon has the capability of removing high amounts of chemical oxygen demand and biological oxygen demand by adsorption. This is an interesting and quite complex system for the purification of water.
In U.S. Pat. No. 4,238,334 there is disclosed a method of various materials for the purification of liquids. The active particulate material that is utilized as the adsorbing material can be an organic polymeric adsorbent, zeolites, bentonite, zirconium oxide, zirconium phosphate, activated alumina, activated carbon or diatomaceous earth. This adsorbent material will also contain a fibrous filter aid substance. The fibrous filter aid substance will have been treated with an electrolytic type of compound that produces a surface charge opposite to the normal charge of such a material. This filter bed is particularly adapted for the removal of suspended solid particles in a water supply.
The prior art is replete with various methods and techniques for the removal of various methods and techniques for the removal of various contaminants from water. Those discussed above relate to various adsorption techniques, Another technique that is utilized is aeration. In aeration a gas such as air is bubbled up through a supply of water and displaces various adsorbed organic and other substances in the water. These displaced substances exit into the atmosphere now having been displaced by air.
However, regardless of these various systems the present adsorbents are a considerable improvement over that which has been utilized in the art. As noted above they will remove over 97 percent of the halocarbon content of a water supply. They will also remove various metal ions including heavy metal ions. In a addition they will remove radon and will be effective in the removal of various microbiological substances. On a weight of contaminant adsorption basis the present adsorption compositions and systems are highly effective. Since they have a high rate of adsorption they can be utilized to process a large volume of water prior to having to be replaced.